Cellulosic composition of matter containing iso-propyl-bromide



July 7, 1931.

S. J. CARROLL CELLULOSIC COMPOSITION OF MATTER CONTAINING I$O-PR0PYL-BROMIDE Filed Aug. 50, 1929 w 93 .2 53523 QEFFZEE 25$ m "M w b Xv O w U 0 g l 5 T m J .1 w m w A m 5 z m m m /V\ r N A). 2D v A I m m m m m m 0 6cm wart matter in which cellulose derivatives,

'lulose ether,

facture of wrapping sheets,

for sensitive photographic coatlngs.

-nishes, lacquers storage or use.

Patented July 7, 1931 ETE STEWART J. CARROLL, or RooHRs'rER, NEW YORKQAssrGNoR T0 EASTMAN KODAK COMPANY, OF ROCHESTER, NEW YORK, A CORPORATION OF NEW YORK oELLULosrc COMPOSITION OF MATTER CONTAINING ISO-PROPYL-BROMIDE Application filed August 30, 1929. Serial No. 389,458.

This invention relates to compositions of such as cellulose acetate, cellulose nitrate or celare combined or mixed with other substances, such as a compatible plasticizer, and a common solvent for both, with or without other useful addition agents, so

that the resulting product will have properties such as will make the composition highly advantageous for use in the plastic and analogous arts, such, for instance, as the manuphotographic film, artificial silk, varnishes or lacquers, and the like.

One object of this invention is to produce a composition of matter which may be made into permanently transparent, strong and flexible sheets or films of desired thinness which are substantially waterproof, are unaflected by ordinary photographic fiuids and possess the desired properties of a support Another object of my invention is to produce a composition which is capable of easy and convenient manipulation in the plastic and analogous arts, such as in the manufacture of sheets, films, artificial silk filaments, varand the like; and to produce a composition which will not injure, or be injured by, the substances or surfaces with which it is associated during manufacture, I Other and further objects will hereinafter become apparent to those skilled in the art to which this invention pertains. I

While cellulose acetates, nitrates and ethers have been known for decades it has also been known that to utilize them in the various plastic arts it is necessary to mix therewith such plasticizing or conditioning agents as camphor, castor oil, triphenyl phosphate, monochlornaphthalene or the like. Certain of these and other addition agents are also added for the purpose of reducing the inflammability of the product. Plastic inducing agent, such as the higher alcohols and their esters, are sometimes also added. Similarly addition compounds of various kinds have been employed to increase flexibility, transparency, toughness and other properties which will enhance the value of the resulting product. Addition products for the same or similar purposes are also added to cellulose acetates, nitrates and ethers to prepare them for use in the other plastic arts, such as in the manufacture of lacquers, varnishes, artificial silk filaments, moulded compounds and the like. WVhile the plasticizers or other addition agents heretofore their utility in the art, the increasing use to which cellulose derivatives have been put may be induced in and/ or contributed to com- I positions conta1n1ng cellulose derivatives,-

such as cellulose acetate, by adding thereto the plasticizing compound iso-propyl-bronude in the presence of a solvent, such as acetone, which will dissolve both the cellulose derivative and plasticizer. is a liquid at ordinary atmospheric temperature and has the structural formula of CH3\O/H 0113 Br It is compatible with cellulose derivatives and particularly compatible with cellulose acetate in the percentages hereinafter given.

It is not an expensive compound and not particularly difficult to produce, or obtain upon the open market. The particularly useful properties which it induces in or contributes to a cellulosiccomposition containing it are hereinafter enumerated.

In order that those skilled in this art may better understand my invention I would state, by way of illustration, that for the manufacture of photographic film or other sheets my new composition of matter may be compounded as follows: 100 partsof acetone soluble cellulose acetate i. e. cellulose acetate containing from 36% to 42% acetylradical, approximately, is dissolved with stirring at atmospheric temperature in 300 to 400 parts,

preferably 400 parts, by weight, of acetone. 100

discovered have had This plasticizer To this solution may be added from 10 to 50 parts by weight, of iso-propyl-bromide, it being found preferable to employ approximately 20 parts thereof. Within the limits stated, the amount of plasticizer may be decreased or increased, depending upon whether it is desired to decrease or increase, respectively, the properties which this plasticizer contributes to the finished product. The amount of solvent employed. may also be decreased or increased, depending upon whether it is desired to have a more or less freely flowing composition, respectively.

A composition of matter prepared as above described may be deposited upon any suitable film forming surface to form a film or sheet, as is well known to those skilled in the art. A film so produced has permanently brilliant transparency and very low inflammability, burning far less readily than ordinary newsprint. Such film is tough and flexible as shown by the fact that it will withstand many folds upon a modified Schopper fold-tester (commonly used for such purposes) without reaking and that even after being subjected for a time to air maintained at a temperature of 56 C. the film still maintains flexibility, demonstating that the film will withstand ordinary usage satisfactorily for a considerable time, whereas a film formed from a mere solution of cellulose acetate in acetone or other similar solvent is brittle and fragile after being subjected to the same treatment for even a much shorter time. 7 The sum total of the above advantageous properties of a product produced from my new composition is considerably in excess of that of products produced with what have previously been regarded as the better plasticizers. 7

Other similar solvents (instead of acetone J which are compatible with the cellulose acetate and my new plasticizer may also occur to those skilled in this art. In like manner this plasticizer may be compounded with other single organic esters of cellulose, such as cellulose propionate, butyrate and the like,

or with mixed organic and/or inorganic esters, such as cellulose acete-stearate, acetemalate, or cellulose nitro-acetate, or with the cellulose ethers, a suitable solvent which will dissolve both the cellulosic derivative and the plasticizer being employed.

The accompanying drawing, forming a part of this application, clearly illustrates the particular advantages of employing my novel plasticizer in the plastic arts. In this drawing there are plotted lines or curves graphically depicting the properties of film produced from a composition containing cellulose acetate and this plasticizer. On the horizontal axis is indicated the various percentages of my plasticizer that may be employed with the cellulosic derivative, this percentage being given in parts added to the cellulose derivative rather than parts of the composition; for instance, 30 parts plasticizer added to 100 parts cellulose acetate is denoted as 30% plasticizer added. On the vertical axis at (a), on the left, is indicated in percentage over the initial flexibility of a film which has been formed as described from my novel composition and which has been subjected to air at 50 C. for 25 hours to free it of solvent; the rate of combustion of that film is also indicated by this same column (a). The curve (A) depicts initial flexibility of the film and the curve (C) depicts the rate of combustion of the filmall with various percentages of my novel plasticizer and all as compared to the respective properties of a film produced from a solution of cellulose acetate in acetone and a hypothetical inert material substituted for the plasticizer as denoted by curve (D) indicating unity of 100%. It will thus be noted that my novel plasticizer has the faculty of giving, to a product produced therefrom, good initial flexibility and an exceptionally low combustion rate, as low as that of the average unplasticized film. The product also maintains its flexibility for a time at elevated temperatures. The preferred percentage of my plasticizer which it is desirable to employ to contribute the property of good initial flexibility or low combustion rate to the final product will be obvious from an inspection of this drawing; the best percentage to employ will depend upon which property it is desired to feature most in the final product.

Inasmuch as my above described composition of matter is quite useful in the production of films and sheets it will be apparent that my new plasticizer may also be employed with advantage in the other branches of the plastic art. For instance, my above described composition of matter may be employed in the manufacture of artificial silk by the dry spinning method. With the proper coagulating bath it may also be employed for wet spinning. It may be desired to employ a composition of different viscosity or evaporation characteristics but this is a mere matter changing the solvent proportion oradding evaporation retardents such is triacetin or other high or intermediate boiling constituents, as has been well known in the art for more than a decade. My novel plasticizer may also be employed with advantage in connection with a number of the known lacquer and varnish formulae with which it may be found to be compatible. In suchcases the plasticizer is usually first put into solution with the cellulose derivative solution and if non-solvents are added for the purpose of cheapening the composition they are added only not precipitate the to such an extent as will derivative from solution.

ther uses within the scope of my invention check sample the Will also suggest themselves to those skilled in the art.

What I claim as my invention, and desire to be secured by Letters Patent of the United 5 States, is:

1. A composition of matter comprising a cellulose derivative and iso-propyl-bromide.

2. A composition of matter comprising cellulose acetate and iso-propyl-bromide.

1 3. A composition of matter comprising 100 parts cellulose acetate and from about to 50 parts, by weight, of iso-propylbromide.

4. A composition of matter comprising 100 parts of cellulose acetate and approximately parts, by Weight, of iso-propyl-bromide. Signed at Rochester, New York, this 27th day of August, 1929.

STEWART J. CARROLL.

CERTIFICATE OF CORRECTION.

Patent No. 1,813,661. Granted July 7, 1% to STEWART J. CARROLL.

it is hereby certified that error appears in the printed specification 0% the above numbered patent requiring correction as follows: Page 2 line 27, for "56 (1." read 65 (1.; line 28, for the misspelled word "demonstating" read demonstrating; and that the said Letters Patent sheeid be read with these cerreetien therein that the same may conferm t0 the record of the case in the Patent Office.

Signed and sealed this 3rd day of November, A. I). 1931.

M. J. Moore,

(Seal) Acting Commissioner of Patents. 

